Sonography in Testicular Trauma and Conditions

Cryptorchidism

• Undescended testicles are smaller and less echogenic than normal testicles.
• Undescended testicles are typically oval with a homogeneous texture.
• The mediastinum is rarely seen in sonograms of undescended testicles.

Testicular Ectopia

• Ectopic testicles can't be moved to the correct scrotal position.
• The most common location for ectopic testicle placement is the superficial inguinal pouch.
• Other potential locations include the perineum, femoral canal, suprapubic area, penis, diaphragm, and other scrotal compartments.

Anorchia

• Unilateral anorchia (monorchidism) is found in 4% of patients with nonpalpable testis.
• Anorchia is more common on the left side.
• Definitive diagnosis relies on surgical evaluation.
• Causes include intrauterine testicular torsion or other decreased vascular supply to the testicle in utero.

Polyorchidism (Testicular Duplication)

• An extremely rare condition.
• The left side is more commonly affected (75%).
• Bilateral cases are present in 5% of cases.
• Associated conditions include malignancy, cryptorchidism, inguinal hernia, and torsion.
• A supernumerary testicle is usually small.

Scrotal Pathology

• Torsion, appendages, fluid collections, trauma, varicocele, inflammation (epididymitis, orchitis, epididymo-orchitis), microlithiasis, and masses are all possible scrotal pathologies.

Torsion

• Interruption of testicular blood supply due to spermatic cord twisting is called torsion.
• Bell clapper deformity is a common cause of torsion. This is when the tunica vaginalis completely surrounds the testis, epididymis, and distal spermatic cord, allowing movement and rotation within the scrotum.
• Torsion is more frequent during adolescence (12-18 years).
• Venous flow is initially affected creating scrotal swelling.
• Loss of arterial flow and testicular ischemia eventually develop with continuation of torsion.
• A 360-degree torsion affects all testicular blood vessels.
• Torsion is a surgical emergency. Prompt surgical intervention within 6 hours of pain onset results in 80% to 100% testicular salvage (saving the testis). 
• Between 6-12 hours salvage rate is 70%, and after 12 hours only 20% are saved. Salvageability is generally not possible after 24 hours.
• Clinical signs include acute onset pain (often during sleep), possible lower abdominal or inguinal pain, swollen testis/scrotum, nausea, vomiting, and malposition of the testicle.
• Enlarged spermatic cord, epididymis, and testicle, lack of intratesticular blood flow, and hypoechoic (low-level) heterogenous testicle are findings suggestive of torsion.
• Hydrocele and a thick scrotal wall can also occur.

Appendages

• Embryologic remnants of tissue, primarily from the testis or epididymis, are considered appendages.
• Appendages can undergo torsion causing scrotal pain, most commonly in prepubertal boys.
• A "blue-dot sign" implies appendix torsion. A calcified, mobile appendix is a scrotal pearl.

Fluid Collections

• Fluid collections occur in a potential space between visceral and parietal tunica vaginalis layers.
• Common conditions in this space include hydrocele, pyocele, and hematocele.

Hydrocele

• Serous fluid accumulation creates a hydrocele, usually a painless scrotal swelling.
• Idiopathic (no identified cause) or associated with epididymo-orchitis and torsion.

Pyocele

• Purulent (pus) fluid accumulation forms a pyocele.
• Pyocele develops when an untreated infection or an abscess ruptures into the tunica vaginalis.

Hematocele

• Blood collection is a hematocele caused by trauma.
• Sonographic appearance varies with injury age. Initially, a hematocele shows numerous, highly visible, movable echoes. In time, it becomes hypoechoic with fluid-fluid levels and internal septations.

Acute Scrotum

• Scrotal trauma, frequently resulting from motor vehicle accidents, athletic injuries, or straddle injuries; painful and often swollen scrotum.
• Possible testicular rupture.

Testicular Rupture/Fracture

• Focal alteration of testicular parenchyma, interruption of the tunica albuginea, irregular testicular contour, and scrotal wall thickening on ultrasound can suggest testicular rupture.
• Blood flow disruption across the surface of the testis, and the presence of a hematocele are also indicative.
• Prompt surgical intervention (within 72 hours) can improve the chances of testicular salvage (up to 90%). Salvage is less common after 72 hours (only 45%).

Hematoma

• Hematomas can be related to trauma, may be large, resulting in testicular displacement.
• Hematomas appear as heterogeneous areas within the scrotum.  Over time, these areas may become more complicated, creating cystic components. Hematomas can involve the testis or epididymis, or they may be contained within the scrotal wall.

Varicocele

• An abnormal dilation of pampiniform plexus veins.
• Most common cause of treatable male infertility.
• More frequent in the left testicle.
• Primary varicocele arises from incompetent venous valves of the spermatic vein or pampiniform plexus, often found on the left side. Nutcracker syndrome may also cause one.
• Secondary varicocele is related to increased pressure in the spermatic vein resulting from conditions including hydronephrosis, hepatomegaly, cirrhosis or other retroperitoneal/abdominal masses.
• Typical symptoms are typically painless, but a palpable extratesticular mass ("bag of worms") may be present. 
• Infertility may also be a symptom..
• Sonography shows numerous, anechoic, tortuous tubes (varicose veins) outside the testicle
• The size and shape of varix changes in response to Valsalva maneuver. (Increased pressure, blood vessels fill)

Scrotal Inflammation

• Inflammation of various scrotal structures (epididymis, testis, or both) leading to acute testicular pain. Factors include leukocytosis, fever, dysuria, urethral discharge, scrotal wall edema, and sexually transmitted diseases.

Epididymitis

• Epididymitis is inflammation of the epididymis, the most common cause of acute scrotal pain in adults. The condition is frequently associated with sexually transmitted infections in younger men.
• Enlarged, hypoechoic epididymis is an ultrasound sign, sometimes with focal or diffuse hyperemia (increased blood flow) seen on color Doppler procedures.

Epididymo-orchitis

• Epididymo-orchitis involves the epididymis (inflammation of the epididymis) and the testis (inflammation of the testis).
• Commonly related to the spread of lower urinary tract infection through the spermatic cord.
• Ultrasound demonstrates signs of epididymitis (enlarged, hypoechoic epididymis) and with or without involvement of the testis, the presence of hyperemia and thickened scrotal wall.
• An infrequent complication, pyocele, might be present in severe cases. This is characterized by pus accumulating between layers of tunica vaginalis.

Microlithiasis

• Numerous echogenic foci (structures giving high level echoes) without acoustic shadowing in the testis are characteristic of microlithiasis. 
• Microcalcifications commonly are less than 3 millimeters.
• Microlithiasis often appears bilaterally.
•  Increased risk of testicular cancer is associated with the complication, although the exact cause is unknown. Conditions such as Cryptorchidism, Klinefelter syndrome, infertility, varicoceles, testicular atrophy, and male pseudohermaphroditism are also common.

Extratesticular Masses

• Most scrotal cysts are extratesticular, typically within the tunica albuginea or epididymis.
• Common extratesticular masses include spermatoceles (cystic dilatations of the efferent ductules of the epididymis, often within the head), epididymal cysts, and tunica albuginea cysts.
• Many extratesticular masses are asymptomatic, but some may be palpable.

Spermatoceles

• Cystic dilatations of efferent ductules of the epididymis, commonly within the epididymal head.
• They often contain proteinaceous fluid and nonviable sperm.
• They may be seen more frequently following a vasectomy.

Epididymal Cysts

• Small, clear cysts situated within the epididymis, containing serous fluid.

Tunica Albuginea Cysts

• Present anywhere along the periphery of the testicle within the tunica albuginea.

Scrotal Hernia

• Scrotal hernias (inguinal hernias) occur when a part of the bowel, omentum, or other structures passes through the inguinal canal and into the scrotum.
• A clinical diagnosis is often sufficient, including examination. However, ultrasound is sometimes helpful for unclear cases.
• Bowel is the most common herniated structure, followed by the omentum.

Tubular Ectasia

• Cystic enlargement of the rete testis is tubular ectasia. The rete testis is located at the hilum of the testis within the mediastinum.
• It is an uncommon, benign condition.
• Associated conditions include spermatoceles, epididymal/testicular cysts, or epididymal obstructions on the same side of dilation.

Intratesticular Cysts

• Intratesticular cysts (cysts within the testis) are more frequent in men over forty. These lesions are typically linked with spermatoceles.
• They frequently present near the mediastinum, either as a singular cyst or multiple cysts of various sizes.

Sperm Granuloma

• Inflammation reaction to extravasation of spermatozoa (sperm leakage) forms a sperm granuloma.
• Most commonly found in vasectomy patients.
• A sperm granuloma may develop anywhere within the epididymis or vas deferens.

Adrenal Rests

• Ectopic adrenal tissue within the testicle; migrates during fetal development.
• Clinical signs include congenital adrenal hyperplasia, elevated adrenocorticotropic hormone (ACTH), and possible Cushing syndrome.
• The sonographic appearance shows bilateral, round, hypoechoic intratesticular masses that frequently lie near the mediastinum.

Testicular Carcinoma

• Uncommon cancer, categorized as germ cell or non-germ cell tumors.
• Highly curable form of cancer.
• Most frequent between ages 20-34.
• Symptoms include painless lumps, testicular enlargement, or vague scrotal discomfort.
• Extratesticular masses are usually benign. Intratesticular masses, however, are more likely malignant until proven otherwise.

Germ Cell Tumors

• 95% of testicular tumors are categorized as germ cell tumors.
• Often highly malignant, they are associated with elevated levels of human chorionic gonadotropin (hCG) and alpha-fetoprotein (AFP).
• Subtypes include seminoma, teratoma, embryonal cell carcinoma, yolk sac tumor, and choriocarcinoma.

Seminoma

• Most common testicular germ cell malignancy, typically in males aged 30-50.
• Clinical signs often include asymptomatic painless scrotal mass, hardening of the testicle, and possibly elevated levels of human chorionic gonadotropin (hCG).
• Sonographic findings are frequently solid, hypoechoic, intratesticular masses. They can exhibit heterogeneity if large.

Teratoma

• Benign tumor, with inherent potential for malignancy.
•  Symptoms may include palpable mass, and possible elevated levels of alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG) if malignant.
•  A heterogeneous mass with calcifications, bone, teeth, cartilage, and hair, is frequent on imaging.

Embryonal Cell Carcinoma

• More aggressive than seminoma.
•  May be palpable and possibly elevated levels of alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG).
•  Appearance on ultrasound is heterogeneous, with cystic components and increased echogenicity due to possible calcifications, hemorrhage, and fibrosis.

Yolk Sac Tumor

• Rare, with a good prognosis.
• Signs may include palpable testicular masses, and raised levels of alpha-fetoprotein (AFP) alone.
• Image characteristics: heterogeneous, with areas of bleeding and calcification.

Choriocarcinoma

• Rare, aggressive tumor.
• May be palpable and elevated levels of human chorionic gonadotropin (hCG) are common.
• A varied ultrasound appearance is characteristic, arising from mixed cell types. There is frequently a heterogeneous mass with areas of hemorrhage, necrosis, and calcifications. Irregular borders are also common.

Non-Germ Cell Tumors

• Usually seen in younger boys, non-germ cell tumors include sex cord-stromal tumors, lymphoma, leukemia, and metastases..

Leydig Cell Tumor

• An uncommon tumor, it is often associated with increased testosterone levels and virilization.
• Sonographically, small and hypoechoic intratesticular masses are common, possibly including cystic areas.

Sertoli Cell Tumor

• An extremely rare tumor, it produces estrogen, resulting in gynecomastia (breast enlargement in males).
• Sonographic findings frequently include a hypoechoic, hypervascular intratesticular mass.

Granulosa Cell Tumor

• A rare condition associated with chromosomal abnormalities.
• Elevated levels of estrogen are common, including gynecomastia.
• Sonograms typically demonstrate hypoechogenicity and hypervascular appearance.

Lymphoma and Leukemia

• Malignant lymphoma (1-7% of testicular cancers) is often bilateral in testicular cases.
• Leukemia often is the next most common secondary testicular neoplasm in children.
• Ultrasound findings might reveal testicular enlargement that spreads to a bilateral (or unilateral) tumor.

Metastasis

• Rare, usually occurs later in life.
• Tumors from prostate or kidneys are common origins of metastases to the testicles.
• Other potential origins include lung, pancreas, bladder, colon, thyroid, or melanoma.
• Ultrasound typically shows bilateral metastases and multiple lesions. Appearance includes hyperechoic, solid hypoechoic masses, or a mixed pattern.